United States: Admissibility Of Biomechanical Expert Testimony

The use of biomechanical evidence is increasingly important as more and more low-impact collisions are followed by claims of excessive injuries and fusion surgeries of questionable necessity. A trial judge in New York Supreme Court, Kings County, recently precluded a biomechanical expert with an MD and PhD from testifying in the matter of Singh v Siddique (2016 NY Slip Op 50987(U)). Many courts around the country are closely scrutinizing this type of expert testimony, and we anticipate "Frye" hearings, in almost all cases, will be requested by plaintiffs in the hope of getting the expert precluded, leaving courts to rule on whether the testimony is sufficiently reliable to be admissible. Lewis Brisbois' New York office continues to argue for the admissibility of biomechanical experts' expected testimony by making sure that their opinions are supported by all necessary evidence in the record, including vehicle model information, crush analysis, peer-reviewed studies, photographs, inspections, and repair records. The following is a review of the Singh case.

The accident – Singh v. Siddique

On October 24, 2011, plaintiff's vehicle was rear-ended by the Defendant's vehicle. Plaintiff claimed various soft-tissue injuries to his neck and back and eventually underwent surgery. The case proceeded to trial and, on March 22, 2016, the jury rendered a verdict on liability in Plaintiff's favor. Thereafter, and before the start of the trial on damages, Plaintiff moved to preclude the testimony of Defendant's biomechanical expert.

Plaintiff's motion in limine

Plaintiff's motion in limine cited decisions regarding the admissibility of biomechanical engineers' testimony and several articles from professional journals supporting the preclusion of such testimony at trial. Plaintiff argued the expert's opinions were unreliable, conclusory, and lacking foundation because the expert did not inspect either vehicle involved in the underlying incident, his calculations were not based on the data from the model of vehicle that Plaintiff was driving, and he failed to consider Plaintiff's body size and position within the vehicle. The expert also did not consider the tire or roadway conditions or Plaintiff's medical records. Plaintiff argued further that the expert could not cite to a study that conclusively correlates "Delta-V" change in vehicle velocity with the presence or absence of bodily injuries in motor vehicle accidents.

Defendant's opposition

Defendant opposed the motion by relying on an excerpt from a book entitled "Reference Manual on Scientific Evidence" and 17 prior decisions on the admissibility of biomechanical testimony. Defendant relied heavily on case law to the effect that biomechanical engineering principles are generally accepted in the scientific community and are therefore admissible, even when the biomechanical engineer lacks a medical degree. Defendant argued further that, at best, any deficiencies in the expert's report may be addressed during cross-examination and that Plaintiff did not provide an expert affidavit supporting his position that biomechanical engineering is speculative and conclusory.

The "Frye" Standard

New York courts apply the "Frye" standard to determine whether expert testimony is admissible. See Frye v United States, 293 F 1013 (DC Cir 1923). As explained by New York's Court of Appeals, the Frye test asks "whether the accepted techniques, when properly performed, generate results accepted as reliable within the scientific community generally," and "while courts will go a long way in admitting expert testimony deduced from a well-recognized scientific principle or discovery, the thing from which the deduction is made must be sufficiently established to have gained general acceptance in the particular field in which it belongs ... It 'emphasizes `counting scientists' votes rather than on verifying the soundness of a scientific conclusion.'"  Parker v Mobil Oil Corp., 7 N.Y.3d 434, 446-7 (2006)(citations omitted).

The Court's decision

Following a Frye hearing, the Court granted the motion and precluded the expert from testifying on the grounds that he had not demonstrated competency in the field of biomechanics as applied to motor vehicle accidents and because his methods of obtaining relevant data did not adhere to accepted standards of reliability in order to support his expert opinions.

Specifically, the Court determined that the expert was to be precluded because:

  • His resume was sparse as to his experience and research in the field of biomechanical engineering with respect to motor vehicle accidents and injuries
  • His measurements with respect to "crush analysis" were taken from a photograph of the vehicle's damage, which the Court found "less than credible"
  • He utilized the average weight and age of vehicle occupants, rather than Plaintiff's weight and age
  • He failed to annex any peer-reviewed articles to validate his methods, in support of his conclusion that Plaintiff's injuries could not have been sustained in the underlying incident
  • The expert's citations to scientific studies were found to be outdated and/or irrelevant
  • He was unable to cite a single study that conclusively correlates the Delta-V change in velocity with bodily injuries in motor vehicle accidents

The Court cautioned that, while biomechanical engineers are generally permitted to testify if their conclusions are supported with proper methodology, the expert must first establish that "the processes and methods employed in formulating his or her opinion adhere to accepted standards of reliability within the field." Otherwise the expert should be precluded.

Broader implications

First, experts must be able to fully demonstrate their expertise. The Court's opinion specifically mentioned the lack of relevant studies, presentations, and research on motor vehicle accidents and injuries cited on the expert's resume and his inability to testify competently based upon peer-reviewed industry standards and data. Experts should ensure that their resumes fully reflect their competency and expertise in their field and be able to bolster the proffered testimony by making their prior studies, reports, presentations, and/or other relevant materials available to the Court. Attorneys should encourage experts in this task when necessary.

Second, attorneys must perform their due diligence with respect to the expert testimony they are seeking to admit and ensure that they have retained experts who are fully aware of their legal obligations to ensure the admissibility of their opinions. Counsel must ensure that the expert disclosure and trial materials fully comply with the case law and thoroughly match the legal requirements for admissibility.

Third, experts should be encouraged to analyze all available physical evidence and be prepared to explain their position if certain evidence is no longer available. As the Court noted, taking measurements of motor vehicle damage from a photograph is simply insufficient, particularly where other evidence, such as repair records, could have been obtained and supplied to the expert and then compared with data from the actual model of vehicle.

Fourth, courts have become significantly more open to testimony from biomechanical engineers provided their opinions are sufficiently grounded and, as noted by the Court's decision, the Second Department will not preclude biomechanical engineers unless a Frye hearing has been conducted (see White v Luna, 139 AD3d 939 (2d Dept. 2016); see also Plate v Palisade Film Delivery Corp., 39 AD3d 835, 837 (2d Dept. 2007); Anderson v Persell, 272 AD2d 733 (3d Dept. 2000); Abramson v Pick Quick Foods Inc., 56 AD3d 702 (2d Dept. 2008) (admitting biomechanical testimony that "the force of the slip and fall was insufficient to cause the femoral prosthesis to break, and that the plaintiff's alleged injuries actually resulted from metal fatigue in the plaintiff's prosthetic device"); Cocca v Conway, 283 AD2d 787(3d Dept. 2001) (admitting testimony of two biomechanical engineers on the question of whether, inter alia, "the average rearward acceleration and the average lateral acceleration of the plaintiff's vehicle were minimal and that the anatomical forces resulting from an impact at the plaintiff's computed accelerations are noninjurious, [and] are well within the range of normal human physiological tolerance")).

The mandatory Frye hearing, prior to preclusion, at the very least ensures that attorneys have the opportunity to create a record with respect to their biomechanical experts, ensuring that the Appellate Division has all of the findings of fact and law available for proper appellate review.

In conclusion, we continue to work closely with biomechanical experts to ensure that their expert testimony will be admissible at trial. Based on the issues outlined in Singh v Siddique and similar authorities, it is vital that biomechanical experts be given the opportunity to inspect the vehicles and review photographs, repair records, vehicle damage estimates, and any other evidence which will support their opinions. The biomechanical expert should also be given the plaintiff's medical records and diagnostic films to review, as well as the deposition testimony of both drivers.

We believe the reasoning of the Singh decision can be overcome by giving the expert sufficient evidence upon which to base their opinions at trial. It is also helpful to retain an expert with an MD and try to get an IME doctor to comment on the likelihood of the injury being caused by the impact.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

To print this article, all you need is to be registered on Mondaq.com.

Click to Login as an existing user or Register so you can print this article.

Similar Articles
Relevancy Powered by MondaqAI
In association with
Related Topics
Similar Articles
Relevancy Powered by MondaqAI
Related Articles
Related Video
Up-coming Events Search
Font Size:
Mondaq on Twitter
Mondaq Free Registration
Gain access to Mondaq global archive of over 375,000 articles covering 200 countries with a personalised News Alert and automatic login on this device.
Mondaq News Alert (some suggested topics and region)
Select Topics
Registration (please scroll down to set your data preferences)

Mondaq Ltd requires you to register and provide information that personally identifies you, including your content preferences, for three primary purposes (full details of Mondaq’s use of your personal data can be found in our Privacy and Cookies Notice):

  • To allow you to personalize the Mondaq websites you are visiting to show content ("Content") relevant to your interests.
  • To enable features such as password reminder, news alerts, email a colleague, and linking from Mondaq (and its affiliate sites) to your website.
  • To produce demographic feedback for our content providers ("Contributors") who contribute Content for free for your use.

Mondaq hopes that our registered users will support us in maintaining our free to view business model by consenting to our use of your personal data as described below.

Mondaq has a "free to view" business model. Our services are paid for by Contributors in exchange for Mondaq providing them with access to information about who accesses their content. Once personal data is transferred to our Contributors they become a data controller of this personal data. They use it to measure the response that their articles are receiving, as a form of market research. They may also use it to provide Mondaq users with information about their products and services.

Details of each Contributor to which your personal data will be transferred is clearly stated within the Content that you access. For full details of how this Contributor will use your personal data, you should review the Contributor’s own Privacy Notice.

Please indicate your preference below:

Yes, I am happy to support Mondaq in maintaining its free to view business model by agreeing to allow Mondaq to share my personal data with Contributors whose Content I access
No, I do not want Mondaq to share my personal data with Contributors

Also please let us know whether you are happy to receive communications promoting products and services offered by Mondaq:

Yes, I am happy to received promotional communications from Mondaq
No, please do not send me promotional communications from Mondaq
Terms & Conditions

Mondaq.com (the Website) is owned and managed by Mondaq Ltd (Mondaq). Mondaq grants you a non-exclusive, revocable licence to access the Website and associated services, such as the Mondaq News Alerts (Services), subject to and in consideration of your compliance with the following terms and conditions of use (Terms). Your use of the Website and/or Services constitutes your agreement to the Terms. Mondaq may terminate your use of the Website and Services if you are in breach of these Terms or if Mondaq decides to terminate the licence granted hereunder for any reason whatsoever.

Use of www.mondaq.com

To Use Mondaq.com you must be: eighteen (18) years old or over; legally capable of entering into binding contracts; and not in any way prohibited by the applicable law to enter into these Terms in the jurisdiction which you are currently located.

You may use the Website as an unregistered user, however, you are required to register as a user if you wish to read the full text of the Content or to receive the Services.

You may not modify, publish, transmit, transfer or sell, reproduce, create derivative works from, distribute, perform, link, display, or in any way exploit any of the Content, in whole or in part, except as expressly permitted in these Terms or with the prior written consent of Mondaq. You may not use electronic or other means to extract details or information from the Content. Nor shall you extract information about users or Contributors in order to offer them any services or products.

In your use of the Website and/or Services you shall: comply with all applicable laws, regulations, directives and legislations which apply to your Use of the Website and/or Services in whatever country you are physically located including without limitation any and all consumer law, export control laws and regulations; provide to us true, correct and accurate information and promptly inform us in the event that any information that you have provided to us changes or becomes inaccurate; notify Mondaq immediately of any circumstances where you have reason to believe that any Intellectual Property Rights or any other rights of any third party may have been infringed; co-operate with reasonable security or other checks or requests for information made by Mondaq from time to time; and at all times be fully liable for the breach of any of these Terms by a third party using your login details to access the Website and/or Services

however, you shall not: do anything likely to impair, interfere with or damage or cause harm or distress to any persons, or the network; do anything that will infringe any Intellectual Property Rights or other rights of Mondaq or any third party; or use the Website, Services and/or Content otherwise than in accordance with these Terms; use any trade marks or service marks of Mondaq or the Contributors, or do anything which may be seen to take unfair advantage of the reputation and goodwill of Mondaq or the Contributors, or the Website, Services and/or Content.

Mondaq reserves the right, in its sole discretion, to take any action that it deems necessary and appropriate in the event it considers that there is a breach or threatened breach of the Terms.

Mondaq’s Rights and Obligations

Unless otherwise expressly set out to the contrary, nothing in these Terms shall serve to transfer from Mondaq to you, any Intellectual Property Rights owned by and/or licensed to Mondaq and all rights, title and interest in and to such Intellectual Property Rights will remain exclusively with Mondaq and/or its licensors.

Mondaq shall use its reasonable endeavours to make the Website and Services available to you at all times, but we cannot guarantee an uninterrupted and fault free service.

Mondaq reserves the right to make changes to the services and/or the Website or part thereof, from time to time, and we may add, remove, modify and/or vary any elements of features and functionalities of the Website or the services.

Mondaq also reserves the right from time to time to monitor your Use of the Website and/or services.


The Content is general information only. It is not intended to constitute legal advice or seek to be the complete and comprehensive statement of the law, nor is it intended to address your specific requirements or provide advice on which reliance should be placed. Mondaq and/or its Contributors and other suppliers make no representations about the suitability of the information contained in the Content for any purpose. All Content provided "as is" without warranty of any kind. Mondaq and/or its Contributors and other suppliers hereby exclude and disclaim all representations, warranties or guarantees with regard to the Content, including all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement. To the maximum extent permitted by law, Mondaq expressly excludes all representations, warranties, obligations, and liabilities arising out of or in connection with all Content. In no event shall Mondaq and/or its respective suppliers be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use of the Content or performance of Mondaq’s Services.


Mondaq may alter or amend these Terms by amending them on the Website. By continuing to Use the Services and/or the Website after such amendment, you will be deemed to have accepted any amendment to these Terms.

These Terms shall be governed by and construed in accordance with the laws of England and Wales and you irrevocably submit to the exclusive jurisdiction of the courts of England and Wales to settle any dispute which may arise out of or in connection with these Terms. If you live outside the United Kingdom, English law shall apply only to the extent that English law shall not deprive you of any legal protection accorded in accordance with the law of the place where you are habitually resident ("Local Law"). In the event English law deprives you of any legal protection which is accorded to you under Local Law, then these terms shall be governed by Local Law and any dispute or claim arising out of or in connection with these Terms shall be subject to the non-exclusive jurisdiction of the courts where you are habitually resident.

You may print and keep a copy of these Terms, which form the entire agreement between you and Mondaq and supersede any other communications or advertising in respect of the Service and/or the Website.

No delay in exercising or non-exercise by you and/or Mondaq of any of its rights under or in connection with these Terms shall operate as a waiver or release of each of your or Mondaq’s right. Rather, any such waiver or release must be specifically granted in writing signed by the party granting it.

If any part of these Terms is held unenforceable, that part shall be enforced to the maximum extent permissible so as to give effect to the intent of the parties, and the Terms shall continue in full force and effect.

Mondaq shall not incur any liability to you on account of any loss or damage resulting from any delay or failure to perform all or any part of these Terms if such delay or failure is caused, in whole or in part, by events, occurrences, or causes beyond the control of Mondaq. Such events, occurrences or causes will include, without limitation, acts of God, strikes, lockouts, server and network failure, riots, acts of war, earthquakes, fire and explosions.

By clicking Register you state you have read and agree to our Terms and Conditions